Shareholders' Equity - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016	Oct. 28, 2015
Schedule Of Equity [Line Items]
Share repurchased	23,826	299,988
Acquisition of treasury stock	$ 284,000	$ 2,847,000	$ 44,000
Shares Retired	23,826	11,805
Stock Repurchase Program, Authorized Amount				$ 20,000,000
2015 Share Repurchase Program [Member]
Schedule Of Equity [Line Items]
Share repurchased		288,183
Acquisition of treasury stock		$ 2,700,000
Restricted Stock [Member]
Schedule Of Equity [Line Items]
Share repurchased		11,805
Acquisition of treasury stock		$ 100,000